Oil-well-sealing device



Nov'. *1",2,' 1929. E. H'. MCMAHAN OIL WELL SEALINGfwvIcE Filed June' 18,* 1924 IN V EN TOR. A/mfr H. M9 MA HAN A TT RNE Y.

Patented' Nave. 12, 1929 H. IQH-AHAN, F VENTURA, CA'LJIOBNIA; KABEL mmm mourant or sun mmm n. mmm, nncmsm) OIL-wmL-SEALING DEVICE Application led .Tune 18,

This invention relates more specifically to a device for sealing the upper end of an oil well casing during the operation of cementing tlre wall 'o f the Well to shut olf a flow of water thereto.

In the cementing of oi] wells, it is customary as each string of casing is lowered 1 cement into the shut off the water that into position to withdraw the drilling tools and introduce a measured quantity of liquid well casing, and then after sealing the u per end of the casing string to introduce fluid above the 'cement' to force the same upwardlyvin the space between thewall of the well and casing to completely may be flowing thereinto. The same procedure isfollowed as each succeed' strin is lowered until the entire wall of t e we has been eiectually sealed from the iow of waterthereto, at which time the perforated liner is lowered into its proper position slightly above the oil sands.

It 1s an important object of my invention to provide a simple device that may be detachably mounted on the upper end of a well casing to eectually seal the same against the pressure of the water introduced for the purpose of forcing the liquid cement into posit-ion.

A further object is to provide a device in which the pressure of the Huid for forcing the liquid cement in place is utilized to operate the same to efectually seal the casing.

Other objects and advantages willbe ap parent from the following description, reference being had to the drawmgs accompanying the same, in which:

Fig. 1 is a central longitudmal section through the upper end of an o1l well, w1th the sealing device in operative posltlon on the casin Fig. 2 1s an enlarged side elevatlon of the device.

Fig. 3 is au enlarged longitudinal section through the sealing devlce secured to the up rend ofawell casin x ig. 4 is a plan view o the sealer.

Referring now more specifically to the drawing, 10 desi ates an oil well, 11 the lowermost string o well casing Jmounted there- 5 in, its end dispod above the'bottom thereof.

1924. Serial No. 720,817.

The upper end section of the string of casing is provided with an internally threaded coupling 12 to which the sealing device is sel cured when it is desired to cement the water off after a drilling` operation.

The sealing device 13, preferably consists of a substantially tubular body member or sleeve 14, 'externally threaded on its lower end for engaging the coupling 12, and open at its upper end. The wall of the bodymember directly above the lower threaded end is provided with diametrically disposed threaded openings l5, 16, in which are screwed the endsof Huid suppl pipes 17, 18, for introducing fluid into t e interior of the casing to force the cement in place as will be more fully explained hereinafter.

Disposed within the body member 14 is a sealing or packing mechanism 19, which pref,- erably consists of a shoe 20 provided with a centrally disposed bore 21, threaded at its lower end and having an annular external flange 22 formed thereon, the upper end of bore 21 being provided with an annular internal flange or abutment 23. Surrounding shoe 20 is an expansible packin member 24, formed of rubber or other suita le material, the thickness of the wall of the packing member being substantially equal to the ace formed between shoe and the body member. The lower end of the packin l member rests on the upper surface of the ange 22, and aA metal ring or bushing 25 disposed on its up r end.

Disposed in the upper endpgf the tubular body member isa cap member 26 having a chambered lower end, and provided on its outer peripheral wall with lockin lugs 27, square in cross section, that are a apted to engage` locking recesses 28 formed in the, upper annular end of the body member to hold the cap in locked engagement with the body member when mounted therein. Cap 26 is provided with a centrally disposed threaded bore 29 which is engaged by an eye bolt 30 having a reduced lower threaded end 31 which extends when the sealing the peripheral walls o the' a plurality of member is assembled within the bore of the cap is provided with air exhaust upper surface of the washer engaging the internal flange 23 of the shoe. The wall ofthe or bleeder ports 35, and directly thereabove -with spanner wrench sockets 36 for quickly releasing the cap from engagement with the expansible member after a sealing operation.

The operation of the device-will be readily discernible from the following' description. When it is desired to cement a section of an oil Well, a measured quantity of liquid cement is introduced into the well through thestring of casing, the usual wooden cylindrical plug 40 is then placed on top of the cement as illustrated in Fig. 1, the mandrel 37 which is in screw threaded connection with the bore-of the shoe being utilized to force the plugdownwardly into the casing when the packer is applied thereto.- The locking lugs are then rotated into engagement with the locking recesses formed in the upper end of the bodyv member. to lock the same to the body. f A wrench is then applied to the squared portion 38 of the eye bolt to force the shoe upwardly into the chambered end of .the cap member, this operation expanding thepacking member circumferentially to lill the annular space between the inner peripheral wall of the body member and shoe kto eectually seal the upper end of the casing against uid pressure.L

Fluid under pressure is then introduced through the Huid supply pipes 17 and 18 to force the plug 40 and the cement disposed therebelow downwardly and then upwardly betweenthe wall of the well and casing, to eectually shut oi any water that may be owing thereinto.

It will be noted that on the introduction of iiuid pressure into the casing above the cement, that the force of the same will act against the lower end of the shoe to further expand the packing member and thus insure an extremely tight seal.

What I claim is: j p

1. A casing head sealing mechanism comprising a vented casing head, an expansible packing member mounted in said headabove the vented openings, and screw operated means connected to the packing member for expanding the same, said packing member adapted to be further expanded automatically on an increase of water pressure within the casing after an expanding operation.

2.- A device of the class described comprising a tubular member adapted toibe secured to the upper end of a well casing having fluid inlet ports leading thereinto, a stationary abutment member detachably secured to the upper end of the tubular member, a movable abutment member mounted therebelow, an expansible member surrounding said movable member, whereby on the introduction or water pressure below said movable member the packing member will be expanded in water tight engagement with the tubular member, and means connected to the movable .abutment member for manually operating` the same, independently of the water pressure. 3. A device of the class described comprising a hollow sleeve having iuid inlet ports leading thereinto adapted to be secured Ito the upper end of a well casing, a stationary abutment member detachably secured to the upper end of said hollow sleeve, a movable abutment member mounted below said stationary member, an expansible packing ring mounted between said abutment members, said movable member adapted to be operated to. expand said packing on the introduction of iuid pressure to the well casing, and mechanical means secured to said stationary abutment member and engagingsaid movable abutment member for expanding saidpacking member independently of uid pressure.

4. A sealing device for sealing they upper end of well casing comprising a tubular member having Huid inlet ports leading thereinto, a cap member detachably securedto the upper end of said tubular member, a shoe member loosely mountedbelow said cap member, an expansible packing ring surrounding said shoe member and engaging said 7cap member, and a shoe adjusting mechanism secured to said cap member for moving said shoe to expand said ring into fluid tight engagement wit said tubular member.

5. A casing head comprising a tubular member adapted to be detachably secured to.t the upper end of a well casing, a stationary abutment member mounted in the upper end of said tubular Imember and detachably secured thereto,vsaid abutment member provided with a centrally disposed threaded bore, a threaded bolt loosely engaging said bore, a hollow movable member having an exterior circular abutment flange on its low end and an interior circular abutment flange at its upper end, the lower end of the threaded bolt extending into said movable member having a nut thereon adapted to engage the interior flange of the movable member on a rotation 0f the threaded bolt to move the hollow movable member upwardly, and a cylindrical fsleeve, formed of an expansible material surrounding said movable member its ends engaging the exterior flange of the movable member and the lower abutment end of the stationary abutment member, whereby i cally expanding the same into Water tight engagement With the Wall of the vented body member on an introduction of water pressure below the same, and screw means connected to the mechanism for manually expanding the packing.

In Witness that I claim the foregoing I have hereunto subscribed my name this 7 day of May, 1924. l

10 EMMET H. MGMAHAN. 

